chickens won't go "home" at night

my hens are about 4.5 months old. when i'm home, i let them out of their run to explore around in our gated side yard until dark. when it starts getting dark out, instead of heading back to their coop, they perch on top of a garden potting bench and huddle together. I have to bribe them back into the run with mealworms, and if it's too dark even that won't work and i have to pick them up and carry them back. once they are in the run, they head back up into the coop for the night.

i had read that to teach them where "home" is you're supposed to leave them in their coop for a few days when you first put them outside - but it was already really hot by that time and leaving them in the coop for days didn't seem like a good idea (overheating, etc.).

now wondering if there's a way to re-train them to go back to the coop at night?